Circuit selector control



P. J. WEAVER CIRCUIT SELECTOR CONTROL Filed Aug. 8, 1962 Jan. 11, 1966 7// /L Y I i w 5 m M m g m Q W J A 9 w m Y Q B United States Patent M 3,228,424 CIRCUTT SELECTOR CGNTROL Paul J. Weaver, Pasadena, Calii., assignor to True-Trace Corporation, El Monte, Calif. a corporation of Connecticut Filed Aug. 8, 1962, Ser. No. 215,596 10 Claims. (Cl. 137-635) This invention relates to a circuit selector.

There are numerous examples, particularly in the field of machine tool controls, Where it is desirable to make a selection among various permutations of circuit connections, and where it is desirable to switch from one permutation to another without going through intervening permutations. For example, in many machine tool circuits it is desirable for some selected three out of perhaps five valves to be open for one setup, and in another setup to have a difierent combination of some of the five valves to be opened. Often in selector controls, two successive control positions are separated by other control positions, and it is necessary in switching from one to the other either to turn the machine off entirely, which is inconvenient and often impractical, or to switch quickly through the other permutations, causing shocks and minor motions in the machine which may be undesirable.

It is an object of this invention to provide a circuit selector having a number of unique positions, each of which corresponds to a selected permutation of circuit connections, wherein selection among the positions may be carried out without actuating any intervening permutations.

A circuit selector according to this device includes a body which has an internal wall that forms a bore having a central axis. There are a plurality of axially spacedapart pairs of inlet and outlet ports connected through the body into said bore. A stem is axially mounted in the bore so as to be both rotatable and axially movable therein. A plurality of circuit actuator means are attached to the body with a portion of each proiecting into the bore. A number of cams are attached to the stem, each of the cams having a peripheral null section and a plurality of radially spaced apart actuating segments. Actuating segments not needed for a given permutation can be removed by snapping or milling them oil. With this arrangement, it is possible for the stem to be shifted so that the peripheral null sections are aligned with all of the circuit control means. The stem is then turned so that the desired cam combination is aligned with respective circuit control means. Then the stem may be axially shifted to actuate the selected permutation of circuit control means.

The above and other features of this invention will be fully understood from the following detailed description and the accompanying drawings in which:

FIG.'1 is a side elevation partly in cutaway cross-section of the presently preferred embodiment of the invention;

FIG. 2 is a cross-section taken at line 22 of FIG. 1;

FIGS. 3 and 4 are end views of one of the cams in FIG. 1; and

FIG. 5 is a cross-section of the body only, taken at line 5-5 of FIG. 1.

The presently preferred embodiment of the invention as shown in FIG. 1, includes a body which may conveniently be square in cross-section. The body includes a number of pairs of axially spaced-apart inlet ports 11' and outlet ports 12. As best shown in FIG. 5, the inlet ports and outlet ports are formed by passages which are drilled through the body so that there is a choice of the side of the body to which a fitting is to be attached.

3,228,424 Patented Jan. 11, 1966 collar will move both axially and rotatably with the stem.

A handle is joined to the stern by pin 19. The stem is mounted so as to be axially and rotatably shiftable with-in the bore, which motions may readily be imparted to it by manipulation of the handle.

Within the bore and mounted to the stem are various sealing and camming devices which will now be described. At the right hand end of the bore near cam 15, there is a conventional sliding seal 21 held to the stem by a retainer nut 22. Near the left hand end of the bore, the stem includes a shoulder 23 which serves to support a stack of cams now to be described.

The cams have some lateral dimensions less than those of the bore, so that a fluid chamber can be formed around each cam. A sliding seal 24 of conventional nature is placed between each pair of cams and at the left end of the stack of cams so as to divide the portion within the stack of cams into individual fluid compartments. Seal 21 closes the right-end compartment.

A typical cam is shown in FIG. 3 with its form m-odified in FIG. 4. With initial reference to FIG. 3, there is shown a cam 25 which is typical of cams 26 and 27. It will be recognized that more or fewer cams may be stacked on to the stem depending on the length of the stem and the number of circuits to be controlled by the mechanism. Only cam 25 will be described in detail, it being understood that the others are like it.

Cam 25 has a cylindrical peripheral null section 28. A hole 29 pierces this section to pass an attachment screw 36 which threads into a screw hole 31 in the stem, thereby mounting the cam for axial and rotatable motion in unison with the stem itself. The cam includes a plurality of actuating segments 32. In the example shown, the cam is initially provided with twelve actuating segments, although it will be understood that more or fewer of them could be provided for any desired setup. Each actuating segment has a ramp portion 33 which slopes with reference to the central axis, and a holder portion 34 which is parallel to the axis. It will thereby be seen that the cams have two radially offset sections, i.e., the null section and the holder portion. An object riding the cams surface will assume a difierent radial position relative to the central axis by virtue of contact with these two sections when angularly aligned therewith. By this arrangement, it is possible to actuate a circuit control means. As best shown in FIG. 3, the actuating segments are spaced apart by spacer segments 35 of different radial projection from the holder portions.

In order to provide for various permutations of actuated combinations, individual ones of the actuating segments can be removed by means such as shipping or milling. A single example of a different combination of actuating segments is shown in FIG. 4, where four individual actuating segments remain after removal of eight of the others. More or fewer, or different, actuating segments could have been removed instead.

In the illustrated embodiment, there are twelve angular stem positions. Each corresponds to one relative position between indexing collar 18 and indexing pin 36, the indexing collar being provided with twelve indexing holes 37 to receive the pin. With the modified cam of FIG. 4, there are only four rotary positions of the stem in which at the particular cam station, circuit control means can be actuated by an actuating segment. In the Other eight positions where the actuating segment has been removed, axial shifting of the stem will have no effect, because no actuating segment is located at that position. With the unmodified cam of FIG. 3, there are twelve live angular settings. Different numbers and different combinations are obviously and easily derived.

One example of one type of circuit control means readily controlled by this device is shown in FIG. 1, in this case a poppet valve for controlling the flow of fluid under pressure such as hydraulic fluid or air. The necessary property of the mean-s is ability to be actuated by varying the radial position of a follower element by contact with a respective cam.

With further reference to circuit control means 40 shown in FIG. 1, it will be observed that the body is provided with a poppet bore 41 and mounting holes 42 by means of which a valve housing 43 can be attached to body 10. It will be understood that various seal-s in the nature of O-rings and the like will be provided in accordance with comm-on practice, but because these form no part of the invention, they are not disclosed in detail here. The valve housing includes a poppet bore 44 wherein which there is seated a spring 45, which is opposed between the valve housing and poppet 46 which tends to force the poppet downward. The spring seats in a sink 47 in the top of the poppet. The poppet carries a peripheral seal 48 which is adapted to close on a seat 49 formed in body 10.

The poppet includes a nose 50 which acts as a cam follower in contacting the respective actuating segment. In order to pressure balance the poppet, a vent passage 51 is drilled from the nose into sink 47. Pressures on opposite sides of the poppet are thereby made identical, and the :springs force is provided only for biasing the poppet nose toward the cam rather than for purposes of holding the valve closed.

Other circuit control means 52, 53 are provided for respective cam stations where cams 26 and 27 serve to actuate them.

It will be evident from the foregoing that a wide range of circuit permutations can be made up by tailoring the cams individually to each of the circuit control means. It will further be evident that the handle can be pulled to the left in FIG. 1 to close all circuits at which time it may be turned to select a new permutation and then that permutation can be actuated by pushing the valve to the right in FIG. 1, thereby going from one circuit permutation to another without going through the other permutations, thereby avoiding an unfavorable feature of convention selector controls.

It will further be understood from an examination of FIG. 1 that the number of cams is immaterial to the invention, one or more being useful. This device is useful both as an off-on arrangement for only one cam-actuated circuit control means, or may be used for as many as are desired, simply by increasing the number of cams on the stem.

This invention is not to be limited by the embodiment shown in the drawings and described in the description which is given by way of illustration and not of limitation, but only in accordance with the scope of the appended claims.

I claim:

1. A circuit selector for selecting permutations of circuit connections among a plurality of circuits, comprising: a body having an internal wall forming a bore with a central axis; an axially extending stem in said bore, said stem being mounted to said body for rotation and axial reciprocation relative thereto and having a first and a second axial position in said bore, said positions being axially spaced from each other, a plurality of cams fixed to said stem so as to be recipro-cable and rotatable therewith, a peripheral null section on each cam, said null section extending around the stem at a first radius; an actuating section axially spaced apart from the null section; a plurality of radially spaced-apart spacer segments in said actuating section, said spacer segments having a second radius; a plurality of actuator sites in said actuating section, an actuator segment being disposed in at least some of said actuator sites, each actuator segment including a ramp portion and a holding portion, the holding portions having a third radius, all holding portions being radially separated by at least one spacer segment, each ramp portion serving axially to interconnect the null section and its respective holding portion; a circuit control means axially opposed to each cam, each circuit means being mounted to the body, and being so disposed and arranged as to be actuated by contact with the actuating segment of its respective cam, and to be deactuated when the null section or spacer segment is axially opposed adjacent to the circuit control means, rotation of the stem while the null sections are axially adjacent to the circuit control means occurring with-out actuation of said circuit control means, and whereby with the stem in the first axial position, the stem can be rotated to a selected rotational position and then axially shifted to actuate circuit control means adjacent to actuating segments then aligned therewith, the sections and segments having the first and second radii causing no actuation and portions having the third radius causing actuation, the third radius being greater than the first and second radii, there being no portion of the null section having a radius sufiicient to cause actuation 2. A circuit selector according to claim 1 in which interacting indexing mean-s are carried by the stem and by the body, whereby the stem is limited to a restricted number of rotational positions When the stem is in an axial position where a circuit control means is actuated.

3. A circuit selector for selecting permutations of ci-rcuit connections among a plurality of circuits, comprising: a body having an internal wall forming a bore with a central axis, and having a plurality of axially spacedapart pairs of inlet ports and outlet ports all opening into the bore; an axially extending stern in said bore, said stem being mounted to said body for rotation and axial re-ciproca'tion relative thereto; and having a first and a second axial position in said bore, said posit-ions being axially spaced from each other, a plurality of cams fixed to said stem so as to be reciprocable and rotatable therewith, a peripheral null section on each cam, said null section extending around the stem at a first radius; an actuating section axially spaced apart from the null section; a plurality of radially spaced-apart spacer segments in said actuating section, said spacer segments having a second radius; a plurality of actuator sites in said actuating section, an actuator segment being disposed in at least some of said actuator sites, each actuator segment including a ramp portion and a holding portion, the holding portions having a third rad-ins, all holding portions being radially separated by at least one spacer segment, each ramp portion serving axially to interconnect the null section and its respective holding portion, respective ports opening into the bore in fluid communication with respective flow chambers; a valve axially opposed to each cam, each valve being mounted to the body in fluid communication with and control of flow through a respective port, and being so disposed and arranged as to be actuated .by contact of a portion of the Valve with the actuating segment of its respective cam, and to be deactuated when the null section is adjacent to the valves, rotation of the stem while the null sections are axially adjacent to the valves occurring without actuation of said valves, and whereby with the stem in the first axial position, the stern can be rotated to a selected rotational position and then axially shifted to actuate valves adjacent to actuating segments then aligned therewith, the sections and segments having the first and second radii causing no actuation and portions having the third radius causing actuation, the third radius being greater than the first and second radii, there being no portion of the null section having a radius sufficient to cause actuation.

4 A circuit selector according to claim 3 in which interacting indexing means are carried by the stem and by the body, whereby the stem is limited to a restricted number of rotational positions when the stem is in an axial posit-ion Where a valve is actuated.

5. A circuit selector according to claim 3 in. which the valves are poppet valves, and in which the poppet includes a nose adapted to ride a respective actuating segment.

6. A circuit selector according to claim 5 in which the actuating segments include a slanted ramp portion contiguous to the null section.

7. A circuit selector according to claim 3 in which the body has a bore, and in which the valve is seated in said bore.

8. A circuit selector according to claim 3 in which an indexing plate and an indexing pin are provided, one on the stem and the other on the body, which limit to a restricted number the rotational positions the stem can assume when a valve is actuated.

9. A circuit selector for selecting circuit connections,

comprising: a body having an internal wall forming a cylindrical bore with a central axis; an axially extending stem in said bore, said stern being mounted to said body for rotation and axial reciprocation relative thereto; a cam fixed to said stern so as to be reciprocable and rotatable therewith; a peripheral null section on the cam; and a plurality of radially spaced-apart, axially aligned actuating segments on the cam axially spaced from the null section, the radial projections of the null section and actuating segments being different, the cam having spacer segments standing between the actuating segments, which have a ditferent radial projection from the actuating segments; and a circuit control means mounted to the body, and being so disposed and arranged as to be actuated by contact with the actuating segment of the cam, and to be deactuated when the null section is adjacent to the circuit control means, rotation of the stem while the null sec- References Cited by the Examiner UNITED STATES PATENTS 1,408,557 3/1922 Yarrington 137-63S XR 2,977,983 4/1961 Headings l37635 FOREIGN PATENTS 27,337 6/ 1931 Australia.

ISADOR WEIL, Primary Examiner.

WILLIAM F. ODEA, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,228,424 January 11, 1966 Paul J. Weaver It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 4, line 60, after "portion," insert sliding seal means between adjacent cams to divide the bore into separate flow chambers;

Signed and sealed this 16th day of July 1968.

(SEAL) Attest:

EDWARD J. BRENNER Commissioner of Patents Edward M. Fletcher, Jr.

Attesting Officer 

1. A CIRCUIT SELECTOR FOR SELECTING PERMUTATIONS OF CIRCUIT CONNECTIONS AMONG A PLURALITY OF CIRCUITS, COMPRISING: A BODY HAVING AN INTERNAL WALL FORMING A BORE WITH A CENTRAL AXIS; AN AXIALLY EXTENDING STEM IN SAID BORE, SAID STEM BEING MOUNTED TO SAID BODY FOR ROTATION AND AXIAL RECIPROCATION RELATIVE THERETO AND HAVING A FIRST AND A SECOND AXIAL POSITION IN SAID BORE, SAID POSITIONS BEING AXIALLY SPACED FROM EACH OTHER, A PLURALITY OF CAMS FIXED TO SAID STEM SO AS TO BE RECIPROCABLE AND ROTATABLE THEREWITH, A PERIPHERAL NULL SECTION ON EACH CAM, SAID NULL SECTION EXTENDING AROUND THE STEM AT A FIRST RADIUS; AN ACTUATING SECTION AXIALLY SPACED APART FROM THE NULL SECTION; A PLURALITY OF RADIALLY SPACED-APART SPACER SEGMENTS IN SAID ACTUATING SECTION, SAID SPACER SEGMENTS HAVING A SECOND RADIUS; A PLURALITY OF ACTUATOR SITES IN SAID ACTUATING SECTION, AN ACTUATOR SEGMENT BEING DISPOSED IN AT LEAST SOME OF SAID ACTUATOR SITES, EACH ACTUATOR SEGMENT INCLUDING A RAMP PORTION AND A HOLDING PORTION, THE HOLDING PORTIONS HAVING A THIRD RADIUS, ALL HOLDING PORTIONS BEING RADIALLY SEPARATED BY AT LEAST ONE SPACER SEGMENT, EACH RAMP PORTION SERVING AXIALLY TO INTERCONNECT THE NULL SECTION AND ITS RESPECTIVE HOLDING PORTION; A CIRCUIT CONTROL MEANS AXIALLY OPPOSED TO EACH CAM, EACH CIRCUIT MEANS BEING MOUNTED TO THE BODY, AND BEING SO DISPOSED AND ARRANGED AS TO BE ACTUATED BY CONTACT WITH THE ACTUATING SEGMENT OF ITS RESPECTIVE CAM, AND TO BE DEACTUATED WHEN THE NULL SECTION OR SPACER SEGMENT IS AXIALLY OPPOSED ADJACENT TO THE CIRCUIT CONTROL MEANS, ROTATION OF THE STEM WHILE THE NULL SECTIONS ARE AXIALLY ADJACENT TO THE CIRCUIT CONTROL MEANS OCCURRING WITHOUT ACTUATION OF SAID CIRCUIT CONTROL MEANS, AND WHEREBY WITH THE STEM IN THE FIRST AXIAL POSITION, THE STEM CAN BE ROTATED TO A SELECTED ROTATIONAL POSITION AND THEN AXIALLY SHIFTED TO ACTUATE CIRCUIT CONTROL MEANS ADJACENT TO ACTUATING SEGMENTS THEN ALIGNED THEREWITH, THE SECTIONS AND SEGMENTS HAVING THE FIRST AND SECOND RADII CAUSING NO ACTUATION AND PORTIONS HAVING THE THIRD RADIUS CAUSING ACTUATION, THE THIRD RADIUS BEING GREATER THAN THE FIRST AND SECOND RADII, THERE BEING NO PORTION OF THE NULL SECTION HAVING A RADIUS SUFFICIENT TO CAUSE ACTUATION. 